• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.10
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• pp.1930-1936
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• 2007

Electronic Navigational Charts(ENCs) are official nautical charts which are equivalent to paper charts with supplementary information. Although their main purpose is to be used for the safe navigation of ships, they also contain much information on coasts and seas which may be interesting to ordinary people. However, there is no easy way to access them because of their specialized data format, access method and visualization. This paper proposes m implementation of SVG for the access and services of ENCs. SVG(Scalable Vector Graphic) makes it possible to make use of Vector graphics for map services in basic internet browsing environment. Implementation of SVG for ENC applications by this research is free of special server side GIS mapping system and client side extra technology. The Implementation of SVG for ENC Applications can be summarized as follows: Firstly, SVG provides spatial information to possess searching engine to embody SVG map. Secondly SVG can provide high-quality vector map graphics and interactive facility without special Internet GIS system. It makes it possible to use services with very low cost. Thirdly, SVG information service targeting on maritime transportation can be used as template, so it can be used dynamically any other purpose such as traffic management and vessel monitoring. Many good characteristics of SVG in mapping at computer screen and reusability of SVG document provide new era of visualization of marine geographic information.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.302-307
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• 2002

To investigate difference of components changes in salt-fermented anchovy, Engaulis japonicus sauce during 18 months fermentation by tank size, various chemical properties were examined at 2$\~$3 months intervals. The contents of total and amino nitrogen, total ATP related compounds increased gradually during 18 months of fermentation, and showed higher content in salt-fermented anchor sauce produced by large tank scale (LTS) product than those of small tank scale (STS) product during fermentation. Hypoxanthine and uric acid were the most abundant in ATP related compounds, ranging from $81.1\%$ to $90.4\%$, The cross point of inosine (HxR) + hypoxanthine (Hx) and uric acid was faster in LTS with 10.3 months fermentation than in STS with 12.6 months fermentation. After 18month of fermentation, the LTS was rich in free amino acids, such as glutamic acid, alanine, aspartic acid, valine, Iysine in that order. On the other hand, the STS was rich in free amino acids, glutamic acid, aspartic acid, alanine, vsine, valine in that order. Absorbance at 453 nm were higher in STS than in STS, but was no difference the rate of increase during fermentation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.410-416
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• 2016

After the Sewol Ferry accident, the importance of maritime safety has been emphasized in Korea. In particular, educational and experience training are not only being conducted for maritime personnel but also in schools and at maritime-related organizations in order to broadly instill maritime safety awareness. Based on SOLAS regulations, safety education for sailors conducted every 10 days passenger boats, and fire-fighting drills and abandon-ship training should be conducted once a month on merchant ships. After the Sewol Ferry accident, the maximum number of trainees was reduced from 40 to 20 in order to improve the effectiveness of these training sessions by requiring all trainees to participate in the actual training. The current training process consists of two steps: textbook-based theoretical training and actual practice. Current training environment provides limited capability from human and facility recourses which limit the numbers of trainee participated and system operation time. By introducing the simulation training, it will improve the trainee skill and performance prior to the on-site training and allow the more effective and rapid progress on actual practice. Therefore, it will be proposed the three-step training method in order to improve the effectiveness on fire-fighting drill in Maritime Safety Education on this study. This study suggests a three step training method that would increase the efficiency of maritime safety education. An image-training step to enhance individual task awareness and equipment usage via simulation techniques after theoretical training has been added. To implement this simulation, a virtual training session will be conducted before actual training, based on knowledge obtained from theoretical training, which is expected to increase the speed with which trainees can adapt during the practical training session. In addition, due to the characteristics of the simulation, repeated training is possible for reaction drills in emergency circumstances and other various scenarios that are difficult to replicate in actual training. The efficiency of training is expected to improve because trainees will have practiced before practical training takes place, which will decrease the time needed for practical training and increase the number of training sessions that can be executed, increasing the efficiency of training overall. This study considers development methods for fire-fighting drill simulations using virtual reality techniques.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.239-247
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• 2008

The objective of this investigation was to examine oxygen consumption (OC) and operculum movement number (OMN) of rainbow trout Oncorhynchus mykiss as a function of changes in water temperature (WT). The WT of the rearing facility was increased from $4^{\circ}C$ to $28^{\circ}C$ stepwise at $1^{\circ}C$ day at each WT (5, 10, 15, 17, 20, 23, 26, and $28^{\circ}C$) then OC and OMN were measured. The OC of the fish increased linearly with WT: O=25.0240 WT+17.5400 in the range of $4{\sim}23^{\circ}C$ However, at 26 and $28^{\circ}C$ the OC declined to around the level at $10^{\circ}C$. The OMN also increased linearly with temperature: OMN=4.4847 WT+59.2150 in the range of $4{\sim}23^{\circ}C$ but at 26 and $28^{\circ}C$ the OMN of the fish dropped slightly. The OC and OMN of the fish showed peak at $23^{\circ}C$ with the lowest values at $4^{\circ}C$. In the range of $4{\sim}23^{\circ}C$, the relationship between OC and OMN of the fish was expressed as a linear equation: OC=0.0923 OMN-308.2100. The OC of fish transferred from $15^{\circ}C$ to certain temperatures without acclimation showed a lower OC at 5 and $10^{\circ}C$ but above $15^{\circ}C$ the OC increased/decreased with temperature. The trout died in temperatures above $28^{\circ}C$ even when acclimated step by step with a $1^{\circ}C$ day increase in WT. In this experiment, a negative physiological changs occurred in the experimental fish at $23^{\circ}C$ suggesting that the optimal physiological temperature range of rainbow trout is $10{\sim}20^{\circ}C$.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.4
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• pp.363-371
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• 2023

To construct a ship, blocks of various sizes must be moved and erected . In this process, lugs are used such that they match the block fastening method and various functions suitable for the characteristics of each shipyard facility. The sizes and shapes of the lugs vary depending on the weight and shape of the block structures. The structure is reinforced by welding the doubling pads to compensate for insufficient rigidity around the holes where the shackle is fastened. As for the method of designing lugs according to lifting loading conditions, a simple calculation based on the beam theory and structural analysis using numerical modeling are performed. In the case of the analytical method, a standardized evaluation method must be established because results may differ depending on the type of element and modeling method. The application of this ambiguous methodology may cause serious safety problems during the process of moving and turning-over blocks. In this study , the effects of various parameters are compared and analyzed through numerical structural analysis to determine the modeling conditions and evaluation method that can evaluate the actual structural response of the lug. The modeling technique that represents the plate part and weld bead around the lug hole provides the most realistic behavior results. The modeling results with the same conditions as those of the actual lug where only the weld bead is connected to the main body of the lug, showed a lower ulimated strength compared with the results obtained by applying the MPC load. The two-dimensional shell element is applied to reduce the modeling and analysis time, and a safety working load was verified to be predicted by reducing the thickness of the doubling pad by 85%. The results of the effects of various parameters reviewed in the study are expected to be used as good reference data for the lug design and safe working load prediction.

• Journal of the Korean Geotechnical Society
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• v.30 no.6
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• pp.23-39
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• 2014

An artificial rainwater reservoir installed in urban areas for recycling rainwater is an eco-friendly facility for reducing storm water effluence. However, in order to recycle the rainwater directly, the artificial rainwater reservoir requires an auxiliary system that can remove non-point source pollutants included in the initial rainfall of urban area. Therefore, the conventional soil filtration technology is adopted to capture non-point source pollutants in an economical and efficient way in the purification system of artificial rainwater reservoirs. In order to satisfy such a demand, clogging characteristics of the sand filter layers with different grain-size distributions were studied with real non-point source pollutants. For this, a series of lab-scale chamber tests were conducted to make a prediction model for removal of non-point source pollutants, based on the clogging theory. The laboratory chamber experiments were carried out by permeating two types of artificially contaminated water through five different types of sand filter layers with different grain-size distributions. The two artificial contaminated waters were made by fine marine-clay particles and real non-point source pollutants collected from motorcar roads of Seoul, Korea. In the laboratory chamber experiments, the concentrations of the artificial contaminated water were measured in terms of TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) and compared with each other to evaluate the performance of sand filter layers. In addition, the accumulated weight of pollutant particles clogged in the sand filter layers was estimated. This paper suggests a prediction model for removal of non-point source pollutants with theoretical consideration of the physical characteristics such as the grain-size distribution and composition, and change in the hydraulic conductivity and porosity of sand filter layers. The lumped parameter ${\theta}$ related with the clogging property was estimated by comparing the accumulated weight of pollutant particles obtained from the laboratory chamber experiments and calculated from the prediction model based on the clogging theory. It is found that the lumped parameter ${\theta}$ has a significant influence on the amount of the pollutant particles clogged in the pores of sand filter layers. In conclusion, according to the clogging prediction model, a double-sand-filter layer consisting of two separate layers: the upper sand-filter layer with the effective particle size of 1.49 mm and the lower sand-filter layer with the effective particle size of 0.93 mm, is proposed as the optimum system for removing non-point source pollutants in the field-sized artificial rainwater reservoir.